Yamal and Hide-the-Decline

When I phoned Jones on the day the emails were published online and asked him what he thought was behind it, he said” It’s about Yamal, I think”.

Pearce continued (p 53):

The word turns up in 100 separate emails, more than ‘hockey stick’ or any other totem of the climate wars. The emails began with it back in 1996 and they ended with it.

Despite Jones’ premonition and its importance both in the Climategate dossier and the controversies immediately preceding Climategate, Yamal and Polar Urals received negligible attention from the “inquiries”, neither site even being mentioned by Kerry Emanuel and his fellow Oxburgh panellists.

I recently submitted an FOI request for a regional chronology combining Yamal, Polar Urals and “other shorter” chronologies referred to in an April 2006 email – a chronology that Kerry Emanuel and the “inquiries” failed to examine. The University of East Anglia, which seems to have been emboldened by the Climategate experience, not only refused to provide the chronology, but refused even to provide a list of the sites that they used to construct the regional chronology.

This refusal prompted me to re-appraise Yamal and its role in the Climategate dossier.

Yamal at the Start and End of the Emails
Although the climate science community has represented Climategate as being about the CRU temperature record, the temperature record is only mentioned in a couple of emails.

The dossier is not about CRUTEM, it’s about the Hockey Stick. And within that debate, the dossier was seemingly constructed with particular attention to Yamal. Pearce’s observation about the Climategate dossier beginning with Yamal is literally true. The very first email (1. 0826209667.txt) is about Yamal – an opening scene wittily described by Michael H. Kelly (not the Michael Kelly of the Oxburgh panel) in an overlooked account of the emails shortly after they became public:

Like an Aristophanes satire, like Hamlet, it opens with two slaves, spear-carriers, little people. Footsoldiers of history, two researchers in a corrupt and impoverished mid-90s Russia schlep through the tundra to take core samples from trees at the behest of the bigger fish in far-off East Anglia. Stepan and Rashit don’t even have their own e-mail address and like characters in some absurdist comedy must pass jointly under the name of Tatiana M. Dedkova. Conscientious and obliging, they strike a human note all through this drama. Their talk is of mundane material concerns, the smallness of funds, the expense of helicopters, the scramble for grants. They are the ones who get their hands dirty, and their vicissitudes periodically revived my interest during the slower stretches of the tale, those otherwise devoted to abstruse details of committee work and other longueurs. ‘We also collected many wood samples from living and dead larches of various ages. But we were bited by many thousands of mosquitos especially small ones.’ They are perhaps the only likeable characters on the establishment side, apart from the exasperated and appalled IT man Harry in the separate ‘Harry_read_me’ document, and I cheered up whenever they appeared.

The relatively unexplored data accompanying the emails is mostly tree ring data and contains interesting tree ring data not otherwise available, some of which I’ve used in today’s post (see below).

And, as Pearce observed, the closing scenes of the Climategate dossier showed CRU’s reaction to a series of posts at Climate Audit on Yamal in October 2009, which, together with the nearby Polar Ural site, had been a longstanding issue at Climate Audit.

The controversy in October 2009 was actually the second major CA dispute involving tree ring chronologies from NW Siberia. The earlier criticism was of CRU’s failure to publish an amendment to the prominent Polar Urals chronology (Briffa et al Nature 1995) to show the impact of measurement data that became available subsequent to the original publication (the availability of new data and its value in firming up the Polar Urals chronology timing is referred to in a 1999 email). As reported here, the new data showed a prominent MWP, contradicting Briffa et al 1995 on a cold 11th century.

CRU’s failure to report the update and the seemingly opportunistic adoption of the hockey-stick shaped Yamal chronology in its place had been the topic of many Climate Audit posts, some of which attracted CRU notice (as evidenced by the emails). I unsuccessfully raised the issue in AR4 review comments. CRU’s written evidence to Muir Russell defended their failure to publish or use an updated Polar Urals chronology on the simple fact that they had never updated or reanalysed their Polar Urals chronology subsequent to its publication:

We had never undertaken any reanalysis of the Polar Urals temperature reconstruction subsequent to its publication in 1995.

Given the shortage of 1000-year chronologies, one would have thought that additional data for the long Polar Urals chronology would have been eagerly awaited by its proponents, but seemingly not.

On the other hand, as Mosher has frequently observed, it is almost characteristic for Briffa to make totally contradictory statements within the same article and their evidence to Muir Russell is no exception. Having clearly said that they never reanalysed Polar Urals, CRU then alluded to reanalysis of the Polar Urals record. I’ll try to analyse this evidence on a future occasion; in the meantime, interested readers should consult the submission themselves.

The October 2009 Controversy

The Yamal issue in October 2009 (on the eve of Climategate) arose out of Briffa et al 2008 (Phil Trans B), the data for which had just become available in late September 2009 through the intercession of the editors of Phil Trans B – a journal not specializing in climate and thus not prepared to abet Team data obstruction.

Briffa et al 2008 purported to show “regional” chronologies for three northern Eurasian areas. One regional chronology combined data over a large area including both Finland and Tornetrask, Sweden. A second regional chronology (Avam-Taymir) substantially expanded the Taymir chronology of Briffa 2000 through the addition of sites from Sidorova 2007 (mentioned in the text) and the Schweingruber network (Briffa et al Nature 1998.) The effect of the additions was to somewhat mitigate the decline in the prior chronology. Both networks were very large in their modern portion – each had well over 100 cores. However, the network labeled as a “regional chronology” for Yamal did not expand from the Briffa 2000 network, even though this network had only a fraction of the sample in the other networks – only 10 cores in 1990 and 5 cores in 1995.

The precedent of the addition of Schweingruber sites at Taimyr raised the question why Schweingruber sites weren’t added to the Yamal network to make a truly regional chronology along the lines of the other two. Aside from nearby Polar Urals, there was even a Schweingruber site at the very location of a large proportion of the subfossil samples used in the Yamal network (Khadyta River, Yamal). I raised this issue at CA in a series of posts (see here). The matter was covered even in mainstream press. Ross stated the issue sharply in a National Post op ed in October 2009 as follows:

Combining data from different samples would not have been an unusual step. Briffa added data from another Schweingruber site to a different composite, from the Taimyr Peninsula. The additional data were gathered more than 400 km away from the primary site. And in that case the primary site had three or four times as many cores to begin with as the Yamal site. Why did he not fill out the Yamal data with the readily-available data from his own coauthor? Why did Briffa seek out additional data for the already well-represented Taimyr site and not for the inadequate Yamal site?

This time, CRU responded with online posts here on October 1, 2009 and here on October 27, 2009. The latter post came only three weeks before Climategate and hasn’t been fully analysed to date.

In the October 27 article, Briffa conceded that the Schweingruber Khadyta River dataset did meet CRU’s criteria for inclusion in a regional chronology (thus contradicting NASA blogger Gavin Schmidt who had sneered at the idea in an earlier real climate post here.) Briffa’s excuse was similar to the one later provided in connection with their failure to report on the updated Polar Urals data. They explained their failure to include the data in a regional chronology as due only to the fact that “we simply did not consider these data at the time”:

Our current practice when selecting data to incorporate in a regional chronology, is to include data exhibiting high levels of common high-frequency variability (i.e. on the basis of high inter-site correlations, where these are calculated using high-pass filtered data). Judged according to this criterion it is entirely appropriate to include the data from the KHAD site (used in McIntyre’s sensitivity test) when constructing a regional chronology for the area. However, we simply did not consider these data at the time, focussing only on the data used in the companion study by Hantemirov and Shiyatov and supplied to us by them.

In evidence to Muir Russell published after the inquiry, they expanded slightly on this “explanation”, re-iterating that they never “considered” the Schweingruber data, adding that the “purpose of the work” reported in Briffa et al 2008 was merely to “reprocess the existing dataset of Hantemirov and Shiyatov”:

McKitrick is implying that we considered and deliberately excluded data from our Yamal chronology. The data that he is referring to were never considered at the time because the purpose of the work reported in Briffa (2000) and Briffa et al. (2008) was to reprocess the existing dataset of Hantemirov and Shiyatov (2002).

This “purpose” is nowhere stated in the actual text of Briffa et al 2008. A reviewer or editor, aware that this was the actual “purpose” of the article, would surely have asked the authors to, for example, describe the differences between the new method and previous methods and to show the actual impact of the new method on the Yamal dataset, none of which is described in the article. Any reviewer, editor or reader of the actual text of Briffa et al 2008 cannot help but presume that its “purpose” was not to show the reprocessing of the Hantemirov and Shiyatov 2002 data, but to present regional chronologies expanding the network of Briffa 2000 though the combination of sites.

In CRU’s evidence to Muir Russell, Briffa, with his characteristic inconsistency, contradicted his earlier statement that they had not “considered” the possibility of additional data. Not only did he contradict this earlier statement, he stated that the original intention and objective of the Briffa et al 2008 article was to produce an “integrated Polar Urals/Yamal series” (along the lines that Climate Audit had wondered about), and that this objective was not pursued only because “it was felt that this work could not be completed in time”:

Some historical context for our 2008 paper might shed some light on this issue. Some time ago we began work on a multi-institution paper intended to describe the sensitivities in producing tree-ring-based climate reconstructions to the methods of chronology construction and subsequent climate calibration, illustrated using the examples of various tree-ring chronologies across northern Eurasia. When we later received a request to submit a paper to a planned themed issue of the Philosophical Transactions of the Royal Society about ‘The boreal forest and global change’, Briffa and colleagues decided to use some of the material to hand in preparing a draft. It was intended that this should describe 3 continuous 2000-year ring-width series, each originally planned to represent the integration of a large-regional data set of subfossil and living tree data. The focus was to be on representing large-regional growth signals and initial comparisons with equivalent regional temperature data. The western, ‘Fennoscandia’, series would incorporate near tree-line pine data from northern Sweden and Finland; the Avam-Taimyr series would integrate larch data from near the Taimyr peninsula tree-line region.

Between these we had intended to explore an integrated Polar Urals/Yamal larch series but it was felt that this work could not be completed in time and Briffa made the decision to reprocess the Yamal ring-width data to hand, using improved standardization techniques, and include this series in the submitted paper.

Hide the Decline

I’ve referred here to Schweingrubers sits. These are of course familiar to readers because the Schweingruber network was the data used in the Briffa MXD reconstruction of hide-the-decline notoriety. As shown below, Yamal is in the heart of hide-the-decline country in northern Siberia. The figure below shows the location of Yamal on the location map ( Figure 1) of Briffa et al 1998 (Nature), a figure that compared 1975-1985 tree ring values to 1935-1945 values (MXD left; ring width right). The graphic on the left also shows the location of Schweingruber sites – plentifully represented in Russia, to say the least. Briffa et al 1998 Figure 2 showed MXD and ring width chronologies from 1880-1992, with the third row in the panel showing a pronounced decline for West Siberia

Figure 1 Spatial patterns of relative tree-growth decline. a, The location (circles) of tree-ring chronologies and the division (black lines) into regional averages. b, The locations (black lines) of the grid-box temperatures used for comparison with the tree growth series. The coloured contours show where the ring density (a) and ring width (b) are enhanced (positive) or suppressed (negative) relative to summer temperature during the period 1975–85 compared to the period 1935–45.

In most scientific endeavours, one presumes that specialists would wonder why Yamal had a huge hockey stick, when it was located in a zone with dozens of sites showing a decline. However, no such reflection took place among paleoclimatologists. None seem to have wondered about the validity of the Yamal proxy. And even though Briffa’s chronology was never being formally published (it was shown only passim in Briffa 2000, which did not even report core counts), its use spread rapidly among paleoclimatologists – I sarcastically termed the Yamal chronology as “cocaine” for paleoclimatologists (bristlecones were, of course, heroin) and, from time to time, reflected on how to insert musical accompaniment from, respectively, Eric Clapton and the Velvet Underground whenever either proxy appeared.

Not only was the Yamal chronology widely adopted, the evidence of a decline in a network of nearly 400 sites (with hundreds of cores, not 10) came to be discounted. In Kerry Emanuel’s recent testimony, he stated that the evidence from the very large Schweingruber network was “provably false”, a position that has not been contradicted by any dendroclimatologist.

The Vaganov Network
As noted above, in their online response of October 2009, CRU conceded that it was entirely legitimate to include the Khadyta River and other sites highly correlated to Yamal in their regional chronology, explaining their inclusion practice as follows:

Our current practice when selecting data to incorporate in a regional chronology, is to include data exhibiting high levels of common high-frequency variability (i.e. on the basis of high inter-site correlations, where these are calculated using high-pass filtered data). Judged according to this criterion it is entirely appropriate to include the data from the KHAD site (used in McIntyre’s sensitivity test) when constructing a regional chronology for the area.

Although they said that they had not previously “considered” the use of additional data, they now said that the best approach to developing a chronology was “making use of all the data to hand”:

So what is the “best” indication of relative ring-width changes in this Yamal region? One approach is to judge this by making use of all the data to hand.

To that end, they stated that they had “taken the opportunity to acquire and incorporate additional data from the 3 original sites” [POR, YAD, JAH]. (The Climategate documents showed that they had actually had this data since 1996 or so). They produced another chronology including this data with the Khadyta River (KHAD) data that I had previously identified, arguing that this new chronology was similar to the original Briffa 2000 and Briffa 2008 chronologies and that therefore their previous failure to report a regional chronology didn’t matter, a viewpoint quickly accepted by the climate science community.

But there are some important loose ends.

The CRU (October 2009) position only permits a “limited hangout” (to borrow the Nixonian phrase.) Khadyta River is only one of dozens of Schweingruber sites, a number of which are close to Yamal. In addition, Eugene Vaganov, a prominent Russian dendrochronologist, had also made a large network (61 sites) in the early 1990s overlapping the Schweingruber network in Russia and many of his sites are also near Yamal. This data was never archived, but became available in the Climategate documents.

The figure below shows a detail from the Briffa et al 1998 location map on which the Schweingruber sites are shown in orange, the Vaganov sites in red, Yamal in limegreen. I’ve also added a box showing 10 degrees east-west of the Yamal sites and 65-70 degrees latitude that I’ve used to extract subsets for comparison. Within this box, there are 20 Vaganov sites and 15 Schweingruber sites, all of which (as shown below) appear to meet the relevant standards for inclusion in a regional chronology.Figure 2. Excerpt from Briffa et al (Nature 1998) Figure 1 showing Western Siberian location.

The next figure shows compares core counts in the Vaganov and Briffa 2009 networks. The Vaganov network has 400-500 cores over most of the 20th century. In contrast, the living tree portion of the Yamal “network” in Briffa (2000) and Briffa et al 2008 had only 17 cores (10 in 1990; 5 – in 1995). The somewhat expanded Limited Hangout network of Briffa 2009 still contained only 11-12% of the number of cores of the Vaganov network and thus falls far short os using “all” the data. (It didn’t even use the Polar Urals data.)

Figure 3. Core counts for Vaganov and Briffa networks.

The effect of using “all the data to hand” is potentially quite dramatic. The graphic below compares the Briffa 2009 chronology (red) to the average of site RCS chronologies for the 20 Vaganov sites in the 10-degree box. As you can see, there is considerable correlation between the two chronologies, though the Briffa version is spikier than the much larger Vaganov network. The discrepancy becomes very pronounced from the 1970s on – the Vagnov network shows the characteristic “decline” in the late 20th century that also characterized the large Schweingruber network, while the Briffa Limited Hangout network surges to new records.

The difference between the two results arises because the difference arising from the closing values of the POR and YAD sites in a small network. If they are added into the 20-site Vaganov network, their influence is diluted, but when there are only two other sites (JAH and KHAD), they still yield high closing values.

I’ve observed on other occasions that the Yamal hockeystick is typically very important in multiproxy reconstructions that don’t use bristlecones. In addition to Briffa 2000 and Briffa et al 2008, it is used in Briffa and Osborn 1999; Mann and Jones 2003; Bradley, Hughes and Diaz 2003; Jones and Mann 2004; Moberg et al 2005; D’Arrigo et al 2006; Osborn and Briffa 2006; Hegerl et al 2007; Mann et al 2008 (blended into the Tornetrask version) and Kaufman et al 2009.

Climategate
The Climategate emails contain much information about Yamal and Polar Urals, none of which is referred to by any of the various “inquiries”. I won’t survey all the emails in this note but will touch on some of the most important.

CRU awareness both of the existence of the updated Polar Urals measurement data (Schweingruber’s polurula dataset) and the close relationship between Polar Urals and Yamal is shown in email 1136918726.txt on Jan 10, 2006 from Wigley to Briffa. (This is also the email in which Wigley wonders whether a “reindeer crapped next to one of the trees”.)

Keith,

Thanx for this. Interesting. However, I do not think your response is very good. Further, there are grammatical and text errors, and (shocking!!) you have spelled McKitrick wrong. This is a sure way to piss them off.

They claim that three cores do not cross-date for TRW. They also say (without results) that the same applies to MXD (these results may be in their Supp. Mat. — I presume you checked this).

So, all you need say is …

(1) TRW was not the only data used for cross-dating.
(2) When MXD is used there are clear t-value peaks, contrary to their claim. You can show your Fig. 4 to prove this.
(3) The 3-core-composite cross-dates with other (well-dated) chronologies (Yamal and Polurula), confirming the MXD-based dating. You can show your Fig. 5 to prove this.

You could say all this in very few words — not many more than I have used above. As it is, your verbosity will leave any reader lost.

There are some problems still. I note that 1032 is not cold in Yamal. Seems odd. Is it cold in *all* of the three chronologies at issue? Or did a reindeer crap next to one of the trees?

Also, there seems to be a one-year offset in the 1020s in your Fig. 6.

I hope this is useful. I really think you have to do (and can do) a better job in combatting the two Ms. If this stuff gets into Nature, you still have a chance to improve it. Personally, I think it would be good for it to appear since, with an improved response, you can make MM look like ignorant idiots.

Tom

This email had been prompted by our submission of short comment criticizing crossdating in the Polar Urals data (Briffa et al 1995), an important element in the medieval-modern comparison of Jones et al 1998, (which I had moved on to after MBH98). In their response, they referred to the close relationship with Yamal (permitting the use of the Yamal chronology for crossdating Polar Urals), but notably did not mention the updated Polar Urals measurements, which we had not referred to in our submission.

Subsequent to the publication of Briffa et al. (1995), completely independent ring-width data have become available for the Yamal area adjacent to Polar Urals (Hantemirov & Shiyatov 2002). Comparisons between ring-width data for each of the early Polar Urals cores under discussion and the Yamal chronology (freely available to MM on my website) all confirm our original dating.

Their response referred to various figures, none of which were provided to us. Nor were the statements in their response correct. Comparisons to the additional Polar Urals measurement data and Yamal confirm our original observation of misdating of the 11th century cores used in Briffa et al 1995 and applied in the Jones et al 1998 reconstruction that is still in use.

Perhaps the most important email concerning Yamal was in April 2006 ( 684. 1146252894.txt ). It was one of only two emails that I referred to in the running text of my own submission to the Parliamentary and Muir Russell committees.

Osborn had emailed Philip Brohan of the UK Met Office (cc Briffa) describing CRU’s three regional chronologies (a single series for each) for the three regions later used in Briffa et al – SCAND, URALS and TAIMY – with the URALS series the defined as “Yamal and Polar Urals long chronologies, plus other shorter ones”. The “other shorter ones” were presumably nearby Schweingruber chronologies – not just Khadyta River. The email:

“SCAND” (which includes the Tornetrask and Finland multi-millennial chronologies, but also some shorter chronologies from the same region). These trees fall mainly within the 3 boxes centred at: 17.5E, 67.5N;22.5E, 67.5N; 27.5E, 67.5N
“URALS” (which includes the Yamal and Polar Urals long chronologies, plus other shorter ones). These fall mainly within these 3 boxes: 52.5E, 67.5N; 62.5E, 62.5N (note this is the only one not at 67.5N); 67.5E, 67.5N

“TAIMYR” (which includes the Taimyr long chronology, plus other shorter ones). These fall mainly within these 4 boxes: 87.5E, 67.5N; 102.5E, 67.5N; 112.5E, 67.5N; 122.5E, 67.5N
We do some analysis at the group scale, and for this we take the JJA temperatures from each box and average to the group scale to obtain a single series from each of SCAND, URALS and TAIMY.

We do some analysis at the overall scale, and for this we take these three group temperature series and average them to get an overall NW Eurasia temperature for boxes with tree chronologies in them.

We did also try using a wider average for the region, including all LAND temperatures from grid boxes within a rectangular region from 12.5E to 127.5E and from 57.5N to 72.5N, but I don’t think it correlated so well against the tree-ring width data (I can’t remember the exact correlations), so we didn’t pursue that.

Does that give you enough information to be going on with? I’d recommend using CRUTEM3 rather than HadCRUT3, because the correlations seem to deteriorate with the inclusion of SST data in some cases — though of course you can look into this yourself.
Cheers
Tim

In March 2007 (780. 1172776463.txt), Osborn again referred to a regional chronology combining Yamal and Polar Urals as being used in a PPT presentation. Osborn noted that revisions to the chronology had made “quite a big change”, thereby getting rid of what had previously been a “higher peak near 1000 AD“:

Here is the old version for you to compare with… the only noticeable difference is for the URALS/YAMAL region, which previously had a higher peak near 1000 AD. Although that was quite a big change, once you average it with the other two series, the overall mean series shows very little difference.
Cheers, Tim

I find the evidence of these emails is hard to reconcile with CRU statements that they had never “considered” updating the Polar Urals chronology, that they had never “considered” adding other chronologies to Yamal to make a regional network and that they had “lacked time” to make a combined Polar Urals/Yamal chronology.

In order for the “inquiries” to properly carry out their obligations, they should, among other things, have obtained the regional chronology referred to in email 1146252894.txt and provided an explanation of why this chronology never appeared. They should also have resolved the apparent contradictions between CRU’s evidence to Muir Russell (and their online statement before Climategate) was that they never “considered” the addition of Schweingruber and other data to make a regional chronology with the evidence of the emails that they had already made such a calculation in April 2006.

I’ll review the conclusions of the inquiries and the reasons for the FOI refusal in following posts.

One wonders how anyone could read all this without having serious doubts as to either: 1) the competence of this crew, or 2) their credibility. Every honest scientist who reads it should begin to question everything he’s heard about the settled science.

Although it might bad form to reply to one’s own post I’ve just realised in my head that if one was to transcribe Gerschwin’s clarinet glissando, from the opening bars of Rhapsody in Blue, into a graph -it would surely resemble a ‘hockey stick’…

Not being an aficionado of the machinations of the “team,” it seems to me that the crux of the thing is in Figs. 1-3. You look at the box in Fig.1, then inspect the opportunity for good sampling statistics evident in Fig. 2, then ask rhetorically why not include all the data. Figure 3 gives the answer; all the data give the ‘wrong answer.’ What am I missing?

The quality of the posts in the past few months has been superb and this one is no different. As Steve’s understanding grows from putting all the pieces together, so too does the understanding of all of us, even those of us who are not well-versed in science.

The most beautiful symphony ever composed is carefully compiled, one thoughtful note at a time.

This most recent resolute analysis adds yet one more stratospheric movement onto the body of Mr. McIntyre’s already engaging and at times awe inspiring body of work.

So far, combined, the composition Steve seems to be edging closer toward, somewhat reminds me of what many consider to be Beethoven’s most meticulous symphony, the 6th. Also known as the “Pastoral Symphony”. Which begins with airy, whimsical, enlightening notes, then builds power throughout the allegros.

Yet today, none of us know which if any of McIntyre’s previous revelations should be considered as, or compared to, Beethoven’s 4th allegro there, known as ‘The Storm”.

However, having enjoyed his determination and skill so immensely to this point, I am absolutely certain that Steve’s magnum opus will be complete when he, not anyone from the “Team”, nor anyone else, chooses to come to a close with it, no doubt as gracefully as it began. And I strongly suspect there may well be several more theater shaking crescendos still to come!

With that, I’ll be stuck here to this chair in eager anticipation, until every one of the lights in this hall have all been completely turned out.

Thank you so much Mr. McIntyre, and now, again, I’ll step out of the way so that you will please continue on with your always very important work.

Remarkable work, Mr. McIntyre. You have the instincts of a true scientist. You shine lights upon the relevant detail and, as you do, you provide explanations of what choices might have been made and what choices were made. You provide understanding. All of the scientific world owes you a great debt, as does all of the world.

And there was me wondering what you had been considering lately. Outstanding work. My late Grandfather would have been seriously impressed. ref: Walter Binks (nuclear and radiation stuff,director NPL, Teddington, England and, trivially, the man who invented those little badges that all workers in radioactive environments necessarily wear… amongst other things)

As a small side note, it has occurred to me that these CRU /Mannian people were not looking at global climate.
Instead they studied local weather and rather unsteadily at that.

It gets harder and yet harder to claim that now is the hotest time “evah”, particularlt when “evah” is just a small bite of time, geologically speaking, and that “now” is just 0.25 percent hotter than it was in 1880, properly expressed in degrees Kelvin, naturally.

Kind of makes you wonder which Russian dendrochronologist (with a hacker friend) is our hero. If this supposition is correct, CRU probably knows who is responsible. Has any Russian lost his paltry funding from CRU lately?

Here is the funding page of the dendrochronology lab in Russia. It seems that the last grant with the Brits ended in 2000. In the years 200-2003 they obtained support from Austria and Switzerland.http://tinyurl.com/3t9e5j3

Glad to see you addressing Yamal/Schweingruber/Polar Urals again. Some of this HAD happened just prior to Climategate and then had gotten totally lost in the (much welcome) hubbub. But it is important stuff!

This is such a long and involved post that I have many comments, but will address just this for now:

Using TRW or MXD as proxy for weather must be done with a lot of caveats, because of the other factors that affect tree ring growth – in particular, nutrients and precipitation.

In re nutrients, let us quote Wigley:

There are some problems still. I note that 1032 is not cold in Yamal. Seems odd. Is it cold in *all* of the three chronologies at issue? Or did a reindeer crap next to one of the trees?

Yes, the man is being facetious (or shall we even say “fecesious”?. But he also knows what they all know – that reindeer crap can affect TRW and MXD. And if it does, what does that do to using TRW and MXD as temperature proxies?

It makes several assertions to tree rings being proxies for precipitation, such as

Baldcypress has proven valuable for the reconstruction of growing season precipitation variability during the late Holocene throughout its native range.

and

This precipitation history recorded by the growth rings of baldcypress trees has proven to be incredibly accurate and has revealed a number of severe, sustained droughts that had a dramatic impact on the natural environment and human affairs.

The baldcypress tree-ring chronologies now available from the southeastern United States and Mexico form an important component of the continent-wide network of
climate sensitive tree-ring chronologies (Figure 13), and have been used to reconstruct spatial patterns of drought and wetness for the past 1000 years.

I would draw special attention to the map entitled “Tree Ring Chronologies,” with its caption

This map illustrates the continent-wide distribution of tree-ring chronologies, most derived from old-growth forests with trees at least 300 years old. Most of these chronologies are sensitive to precipitation and have been used as proxies for the reconstruction of past drought years and wet years.

The impact this has on using tree rings as proxies for temperatures has to be serious. Tree rings cannot be looked at as solely temperature or solely precipitation (or solely reindeer crap). Unless someone can tell precisely which component(s) of TRW or MXD are applicable as proxies to temps and which to nutrients and which to precip, all we have is a muddle.

I totally agree, that tree rings are affected by temperature. I also totally agree that tree rings are affected by precipitation, and by nutrients (thank you, Dr. Wigley!). But how much can we assign to each? To read backwards from TRW or MXD and say how much of each is from each forcing, has anyone done that? And if so, how reliable is the separation?

I would strongly suggest its never been done.

In its absence – or even if it has been done – any study that asserts TRW or MXD as a proxy for ANY factor needs to present caveats, such as, “While we are using tree rings as proxies for temperature, we must also mention that tree rings are also proxies for precipitation, and this has been dealt with by doing X, Y and Z in our calculations. It is a widely known fact that precipitation does not follow temperatures; therefore additional uncertainty must be understood in our conclusions. We estimate the additional uncertainty to be +/-___°C. In addition, it should be understood that this uncertainty must be a first-order uncertainty, meaning the line on our graph is itself not a line, but a band that percentage wide, before ever including the other uncertainties depicted in our graphs.”

Perhaps every paper needs to have a section named “Uncertainties Dealt With.”

Due to this, I have come to conclude that tree rings are not a suitable proxy for past temperatures. The divergence “problem” of Briffa (post-1960 and pre-1550) and Schweingruber when compared to the recent instrument data should perk everyone’s ears up and raise eyebrows for real.

The use of tree rings as proxies for temperatures OR precipitation needs to be closely re-examined. BOTH factors are present, always, and their combined effects must vary widely. Some years may be wet and cool, while others may be warm and only reasonably wet; both would appear more or less the same. Warm years without rain would not show much growth of tree rings.

SteveG, please consider taking a brief pass back through you excellent post to edit it into an email to Judith Curry and then send it to her at judith.curry@eas.gatech.edu with a request that she consider using it as the basis for a new thread at Climate Etc. She has had several interesting threads on the topic of uncertainty but they tended to be general in nature. The specificity with which you address uncertainty in regard to TRW and MXD should prompt an interesting discussion.

In the meantime, I just got directed to this post at WUWT from 2009, about “Leibig’s Barrel”:

This sheds some light on this, saying that at any given time there is one “nutrient” (considering sunlight, water, CO2, temperatures and other factors all as nutrients for the moment) that is in “shortest supply,” meaning its lack is inhibiting TRW and MXD. This makes sense and would simplify (IMHO) studies on tree rings and their forcings.

I may be oversimplifying it, but this could actually explain the “divergence problem” for Briffa, both in post-1960 instrumented years and in the pre-1550 era.

I assume that photosynthesis is proportional to tree ring growth, though I wouldn’t state it as fact.

That both pre-1550 and post-1960 have this divergence (at least in Briffa’s collected data) implies that the MWP DID exist and that the present day may truly be approaching the MWP in temps.

At the same time, precipitation IS a factor, too. I suggest a quick read of the post at WUWT dated 9-28-2009, only weeks prior to Climategate. The point is made that studies should be done on control trees, and I would heartily agree, though I would not see it necessarily getting rid of the problem of isolating warmth from precipitation. But it may lead to more reliable methods.

In the meantime, I don’t see how tree rings can be used as proxies for temp AND precip.

Steve – please comment on Yamal rather than generic arguments about tree rings.

You remarked on the difficulty of interpreting tree ring data in terms of climate variables and wondered whether it was feasible.

There is a web page produced by Osborne and Briffa in which they discuss their selection of tree ring data, and give some details about the data and discussed the uses of the different data sets in their papers. One point they make about the schweingruber data is as follows:

Various subsets of this data set have been used in a number of studies published by Keith Briffa, Tim Osborn and other colleagues at the Climatic Research Unit (see below for references). In particular, the focus of our work has been mostly on data measured from tree-core samples that were collected at relatively cool and moist sites. These sites are generally at high elevation or high latitude, covering much of the Northern Hemisphere between 20 and 75°N.

They go on to describe the data used for 15 papers published between 1997 and 2005.
Over this period of time, they studied how tree rings reflected the various influences on growth, temperature, soil, moisture etc. They also point out the divergence phenomenon that they studied.

I am not familiar enough with the literature to understand their work in any detail, but given the work the authors have put into this subject over the years, it seems to me that their knowledge of the applicability of tree rings as proxies for temperature or other variables, and their work, should be respected, whether or not one agrees with their conclusions.

As far as the larger picture is concerned, I find it hard to believe, given the large evidence from number of proxies which contain no tree ring data, and the temperature record, that shooting down the idea of using tree rings as temperature proxies is going to overturn the idea that the global warming in the last millenium is unprecedented.

Steve: the realclimate post cannot be relied on. For example, the Mann “no dendro” reconstruction uses upside down Tiljander sediments, the modern portion of which has been contaminated by bridge sediments. They have refused to acknowledge this. Other examples in the post go back only 500 years through the LIA.

The degree to which the results depend on bristlecones and/or Yamal is quite surprising.

Steve – please comment on Yamal rather than generic arguments about tree rings.

Geoff, I recall that quite some time ago there was some discussion about a description of Steve as a gadfly. That said his theme music must be the romance from the Gadfly Suite of Dmitri Shostakovich. Connection to “Reilly, Ace of Spies” fully intended.
Pat

You can get a lot of the drift from Russia from the half dozen emails that pop up when you search “money”. Reading between the lines, those poor Russian slaves were hung out to dry with funding games by UEA. I have not seen much credit going their way.

Which then obviously begs the question – why are the scientists who felt duped by climate gate not pursuing this? I’ll refrain from posting my speculative thoughts, in the sure knowledge that anybody who has been reading these posts can come up with a suitable answer themselves …

from the referenced briffa reply
“Raw Data Availability
Briffa has also been attacked by McIntyre for not releasing the original ring-width measurement records from which the various chronologies discussed in Briffa (2000) and Briffa et al. (2008) were made. We would like to reiterate that these data were never “owned” by the Climatic Research Unit (CRU) and we have never had the right to distribute them. These data were acquired in the context of collaborative research with colleagues who developed them. Requests for these data have been redirected towards the appropriate institutions and individuals. When the Briffa (2000) paper was published, release of these data was specifically embargoed by our colleagues who were still working towards further publications using them. Following publication of the 2008 paper, at the request of the Royal Society, Briffa approached colleagues in Sweden, Ekaterinburg and Krasnoyarsk and their permission was given to release the data. This was done in 2008 and 2009. Incidentally, we understand that Rashit Hantemirov sent McIntyre the Yamal data used in the papers cited above at his request as early as 2nd February, 2004.”

Is it true that McIntyre had the data since 2004?
Is it true that CRU did not own the data and could therefore not distribute it?

Steve: MY principal issue was the failure to present a regional chronology for Yamal incorporating Schweingruber and other available data.

The Taymir and Tornetrask RW data were unavailable until Sept 2009 despite repeated requests. I had a Yamal version used in Hantemirov and Shiyatov 2002, but did not know whether this had been used in the RCS reconstruction of Briffa 2000 (which did not provide core count information so that provenance could be confirmed.)

If scientists publish articles that are then used by IPCC, they should ensure that they have the right to show their data. Mutual fingerpointing from one scientist to another is unedifying.

They passed the requests on to the owners of the data (surely this is the correct procedure?). The owners seem to have sent McIntyre the data in 2004

Steve: As I already said to you, the Taymir and Tornetrask RW data were unavailable until Sept 2009 despite repeated requests. I had a Yamal version used in Hantemirov and Shiyatov 2002, but did not know whether this had been used in the RCS reconstruction of Briffa 2000 (which did not provide core count information so that provenance could be confirmed.)

ThePrefercTFord (and the likes) apparently imputes MacSteve with supernatural forces to know which data has been used without telling him? Or maybe they assume that, besides a computer, MacSteve uses a crystal ball?

And they still don’t understand that selecting your proxies by how well they correlate with climate (and picking also the “best” local climate data to use) is cherry picking likely to create spurious correlation (a term that also seems beyond the Team vocabulary). Until they use “all” the data rather than stopping the analysis of a region when they get a “good” result, the whole enterprise is suspect.

Craig Loehle, has this been covered anywhere. I find it irritating in various papers that they start with an evaluation of how well tree rings correlate with temperature in various seasons, months, or even 8 day periods, and take the good correlations to mean that trees are now representing the temperature in those months.

Please note that the Michael (Horatio) Kelly in this blog entry has nothing to do with me, the Michael (Joseph) Kelly who was a member of the Oxburgh Review Committee, whose notes on the science at CRU were discovered by you in an FOI enquiry of another member of the Oxburgh panel. The notes have been subsequently read into the UK Parliamentary record. I stand by what I wrote.
Michael Kelly
University of Cambridge
Steve: thanks for checking. I’ve clarified that point in the text. Also, your notes to the Oxburgh panel were a rare bit of common sense in this entire matter. I’ll bite my tongue for now on editorializing about the report itself (which I’ve done on other occasions.) I’m going to do a post on Oxburgh and Yamal in a day or two.

Perhaps you can clarify something for me. Kerry Emanuel told an associate (who passed this on to me) that Phil Jones had told the Oxburgh panel that it was probably impossible to do the reconstructions with any accuracy. As far as I was concerned, this was the point at issue. I asked Oxburgh to confirm this and he said that “science” was not the subject of their inquiry. The science questions remain of interest to some of us – can you confirm whether Jones told this to the panel.

Steve,
I honestly do not recall that particular interchange a year later. As the report stated, we did not actually review the science per se.
MJK

Steve: Jones’ statement that it was probably impossible to do the reconstructions with any accuracy, if made, bears on the disclosure in the their articles and in IPCC and, in my opinion, was well within your terms of reference, however defined. BTW, to my recollection, the report does not state that you did not “review the science per se”. That observation was made in a subsequent email.

One of the reasons why most inquiries take transcripts is precisely because people don’t always remember things. The Parliamentary Committee had strongly encouraged the inquiries to adhere to proper process and it is too bad that the Oxburgh panel failed to do so. It might well have prevented that cynicism about this panel felt by myself and others.

from the same paperhttp://www.cru.uea.ac.uk/cru/people/briffa/yamal2009/
“We wish to stress that McIntyre himself has made no such assertions. At no time does he suggest that either of his versions of the chronology represents general Yamal tree-growth changes “more realistically” than in our earlier work. However, his original posting has been interpreted in this way by others, both on the Climate Audit website and elsewhere. Some postings on Climate Audit, notably that by Ross McKitrick (comment no. 7), strongly imply that the data used in the published versions of the Yamal chronology were deliberately selected in order to manufacture misleading evidence of a recent tree-growth increase in this region. Subsequent reports of McIntyre’s blog (e.g. in The Telegraph, The Register and The Spectator) amount to hysterical, even defamatory misrepresentations, not only of our work but also of the content of the original McIntyre blog, by using words such as ‘scam’, ‘scandal’, ‘lie’, and ‘fraudulent’ with respect to our work.

Our current practice when selecting data to incorporate in a regional chronology, is to include data exhibiting high levels of common high-frequency variability (i.e. on the basis of high inter-site correlations, where these are calculated using high-pass filtered data). Judged according to this criterion it is entirely appropriate to include the data from the KHAD site (used in McIntyre’s sensitivity test) when constructing a regional chronology for the area. However, we simply did not consider these data at the time, focussing only on the data used in the companion study by Hantemirov and Shiyatov and supplied to us by them.

We would never select or manipulate data in order to arrive at some preconceived or regionally unrepresentative result. However, as we will show here, the fact that we did not incorporate the KHAD data has no serious implications for the general validity of our published work. ”

Steve: They say: “However, we simply did not consider these data at the time, focussing only on the data used in the companion study by Hantemirov and Shiyatov and supplied to us by them.”

My question is how this statement reconciles with the email reference to a regional chronology combining Yamal, Polar Urals and other shorter chroncologies. The statements seem inconsistent to me – perhaps you can clarify the inconsistency?

from the same paper:
“McIntyre states “If the non-robustness observed here prove out .. this will have an important impact on many multiproxy studies …”. We have shown here that the “KHAD only” example constructed by McIntyre itself represents a biased chronology, contradicted by the evidence of other chronologies constructed using additional and more representative site data. The evidence does not support a conclusion that our previous work was in any way seriously flawed. The last 8 years of our chronology ARE based on data from a decreasing number of sites and trees and this smaller available sample does emphasise the faster growing trees, so this section of the chronology should be used cautiously. The reworked chronology, based on all of the currently available data is similar to our previously published versions of the Yamal chronology demonstrating that our earlier work presents a defensible and reasonable indication of tree growth changes during the 20th century, and in the context of long-term changes reconstructed over the last two millennia in the vicinity of the larch treeline in southern Yamal. ”

McIntyre, are you therefore calling them liars?

Steve: I avoid using inflammatory words like “liar”. Possibly there’s an explanation of the inconsistency that I haven’t thought of. I do think that the issues deserved to be investigated. Perhaps an actual investigation would have explained the inconsistency. It’s too bad that the issues weren’t investigated.

Even a cursory examination of outliers, as done at CA, shows that Yamal trees represent six sigma excursions compared to the general population (and bristlecones are similar in this respect). In both cases, there is an alternative explanation for the growth surges related to change in growth form (Yamal larch) or recovery from damage (bristlecones) that is unrelated to climate. This makes these two data sources something to be avoided, and the excuse of these data meeting their “standard criteria” simply does not hold water. Do these guys know nothing about the trees they drill?

“We did also try using a wider average for the region, including all LAND temperatures from grid boxes within a rectangular region from 12.5E to 127.5E and from 57.5N to 72.5N, but I don’t think it correlated so well against the tree-ring width data (I can’t remember the exact correlations), so we didn’t pursue that.”

It’s so climate science. Cast around for the temperature series that matches your data best then use that one because since it matches, it MUST be what drives the data. If their wider region matched better they’d have used it, but because the other matched better they use that instead – totally blinded by their confirmation bias.

We recently, reluctantly, have had to have a tree in our front garden cut down for structural reasons. Looking at the stump it is clear in many rings that they are much wider in some parts than others.

Now presumably if I had taken cores from this tree for research purposes the results I might infer would be different depending on the precise area where the cores were taken. Moreover this one tree seems to indicate differential growth in any particular year, so how do dendros correct for this?

Hm, being a layman myself I’ll try to understand the importance of this in a broader context in layman’s terms, please correct me anyone where I’m wrong, or if I’m “going a bridge too far”:

1) The “big picture” is that the “Team” sought to

A) In the TAR: present “independent” studies that “confirm”, or give more or less the same overall picture of NH last 1000 years temperature history as the hockey stick (MBH98 & 99). The aim was to provide a justification for the TAR’s message: that temperatures today are “unprecedented in the last thousand years”.

B) In the AR4: salvage the hockey stick from the TAR so that it could be kept in the AR4, after the criticisms in peer reviewed papers from MM, the NAS and the Wegman report.

2) To be able do A and B they seem to have

A) Cut off (or even modified) all “adverse” data, that is, data that differed too much from the hockey stick, including data that differed from the temperature record, thereby putting the ability of these trees to produce any information about temperatures into question (the “divergence problem”/”hide the decline”) after 1960, and also pre-1550 data, using various versions of “the Trick”. The post above shows how the Team has preferred an extremely thin data sample (only a few trees) of hockey stick shape in an area characterized by a more general “decline” in lots of other data.

B) This way they were able to produce a combined graph, or should we say a spaghetti meal for the regulars at the IPCC Cafe, cooked on various hockey sticks using a small subset of “active (spicy?) ingredients” like “magic” bristlecones, certain lake sediments study used upside down (Tiljander) or a couple of trees in Yamal in order to present a consistent or coherent “storyline” for the IPCC reports.

I guess the importance of all this is that this part of the IPCC reports is not based on studies, and/or data, and/or treatment of data that can be said to make up a “robust” fundament for the claim that the warmth in different locations during the Mediaeval Warm Period was just a “local” or “regional” phenomenon.

The referenced literature of the IPCC – which is basically the Team’s studies, now proven “not robust” – just can’t justify such a claim (or any claim to the contrary for that matter).

The leaked e-mails show that the Russian researcher who collected the tree-ring data observed that the trees line had not moved north as would be expected if climate warming had occurred. I attach an excerpt from the leaked e-mail (document 907975032.txt):

I apologize for delay with reply. Below is short information about state of Yamal work. Samples from 2,172 subfossil larches (appr. 95% of all samples), spruces (5%) and birches (solitary finding) have been collected within a region centered on about 67030’N, 70000’E at the southern part of Yamal Peninsula. All of them have been measured.

[SNIPPED, except for the last sentence.]

There are no evidences of moving polar timberline to the north during last century.

That is one of my reasons for being stupefied when people call CRU’s data processing “climatology” and arguing that people like Steve M. just cannot understand the science. All CRU does is collate (very poorly) and statistical processing.

That CRU did not think it necessary to have a real statistician on staff is, frankly, unbelievable. (If I am wrong on that, someone please correct me…)

One must believe that the statistical capabilities of the separate Team members varied, perhaps widely. Judging by Harry_Read_Me, the lower end of that range was pretty low.

The primary criticisms I’ve seen against Steve’s Yamal post were that he actually had the data from the Russians, so complaining about Briffa’s intransigence is foolish, as this was the first time that they were coauthors. I don’t see how being a coauthor changes anything with regards to data availability.

Second criticism is that McIntyre has taken data which are known to be wrong based on the temperature record and added them to form an alternative reconstruction, and this is bad science. However, updated Polar Urals also correlates to the local temperature record, and it doesn’t show the same level of growth in redent decades.

Steve: there has been lots of disinformation. I had “some” data, but didn’t have data for Taymir (or Tronetrask), which was important for the analysis. The second “criticism” is not one that Briffa advanced. Briffa’s defence was that they could still “get” something similar by adding data that had not then been reported.

And it’s not just Polar Urals. There are dozens of sites showing the decline. Briffa’s Porza and YAD sites are the exceptions.

I think it’s also fair to add that some of the “he already had the data when he was asking for it” sniping from climate scientists concerning yamal data were a result of climate scientists being deliberately obtuse in requests as to where particular data had come from. They coyly refused to state it – even though (as I understand it), he already had copies from it as part of a larger series of data which he already had access to. ie they apparently expected him to recognise a subset of data he already had, yet would not simply divulge it when asked. This instance of petty and pathetic behaviour by the climate scientists (and their subsequent crowing about it) was the straw which finally put me in the mode of thought that everything they produce must be doubted until proven true, rather than accepted until proven false. They are simply too cynical in their approach, and too willing to sweep their dirty secrets under the carpet.

So the work could be complete garbage yet not concern the panel? So the panel went about investigating “misconduct” by interviewing the subjects of the inquiry, and no one critical of their work, to reach its conclusions? And it didn’t even record those interviews? Was it the thinking of the esteemed panel members that the subjects would just confess if they had acted inappropriately?

I wonder if panel members might forgive the public for considering such a non-effort as embarrassing or worse.

One of things that has stood out for me in this area is the way the climate science acts in ways other areas of science don’t. Normal scientists are data monsters, they simple cannot get enough of the stuff, there always looking to use more people or more experiments to generate more data. Now partly that because the greater the level of data the more real world implications and validity the results have , but also because it helps to justify the expensive computing power while keeping the scientists mathematical profile high .

However, in climate science, the hunt for data is a rather odd one, where good data is rejected and the amount of data used can be tiny. Let’s be honest if any other area where to make the bold and world wide ranging claims off such small amounts of data they would be laughed at , the idea that one tree is representing the climate conditions for the world really is mad .

Any undergraduate will be taught that it’s not possible to extended the results seen in tiny population to the world in general in any meaningful way. How professional ‘scientists’ can be ignorant of this is a mystery.

Keith Briffas obvious desire to “scale up” the current warm period is obvious in climategate e-mail number 1029966978.txt. Predating the publication of Hantemiro & Shiyatov 2002 Hantemirov thanks Briffa for his editing of their research findings, Hantemirov wrights to Briffa:

thank you very much for editing our paper.
It’s a pity you strike your name off the list of authors, you
make an important contribution to writing paper. Your corrections
and additions surely improve paper.

I would only notice the next sentence (page 8):

‘The low interannual variability and the minimum occurrence of
cold extremes during the 20th century, argue that the most recent
decades of this long summer record represent the most favourable
climate conditions for tree growth within the last four
millennia.’

I’m not sure that this statement follows unambiguous from results
presented in this paper. Because mean temperatures during last
decades, according presented reconstruction, are not exceptional.
Besides, e.g. period about 1700 BC, according this
reconstruction, represent probably the same conditions taking
into account low variability, low occurrence of extremes and high
mean temperature.
May be to soften this statement and replace ‘the most favourable’
with something like ‘highly favourably’ or ‘probably the most
favourable’?

The e-mails include a number of subjects, but the temperature data is more likely based on the title. Or perhaps something to do with IPCC procedures. There were no Yamal related FOIs that I’m aware of. That Phil Jones thought it was Yamal is interesting though.

Where does this data come from – Steve seems to say he found it in the climategate files, but it is not clear to me which email or file.
Steve: in documents/briffa-treering-external/stepan. To decode the Vaganov locations, I recalled that there was some information from a now-deleted MBH98 directory. I posted on this last year.

SteveGinIL, Isn’t the theory of using trees near the tree line that temperature is the limiting growth factor? (Much debate about the validity of that, of course. Some people in CA/WUWT have suggested water flow near roots could affect growth rate even near the tree line – and I suppose lack of water due to soil (very porus) or rocky could reduce rate.)

Hence, how do trees in the southern US qualify?

(The report you refer to suggests some of the fossilized trees date back into the last ice age era (which ended 10,000 years ago according to Encarta 2005, the Pleistocene era), but shows some of that type of tree living today in the same area and says ones found in the DC area are north of their present range. IOW, baldy cypress does not grow near the tree line per se – though it has its own limit of range, is that supposedly determined by temperature?)

BTW, interesting reference in the paper to tree fossils found at 82N – that’s very far north, 2 degrees more latitude than the Eureka weather station. Did someone say recent temperatures are unprecedented? 🙂 (Or did the earth gyrate – I recall magnetic poles have moved radically in the past.)

I’ve come back to read this after the recent FOI refusal report, the rolling story is making a lot more sense now. Apart from minor grammar issues there is one thing that might require attention. Regarding Figure 2, reference is made to “20 Vaganov sites and 15 Schweingruber sites” being “within the box”. Looking at the Vaganov sites alone 6 of the 20 locations are outside the box. For Schweingruber a similar inconsistency exists. Perhaps the “box” is the larger box constituting the image itself.

Hope I don’t over speculate with the following. I used to think that the instrument record must be accurate and the “declines” were simply a result of failing proxies, sorted out via the ‘tricks’. Now on reflection I don’t see why such a small region of the earth must necessarily follow the global trend, and it could well be the larger tree network is accurate in stalling around mid 20th century. This is not to cast doubt on the global instrument record but rather to suggest there may be a divergence between it and this particular region favoured as a tree ring source.

Steve: the site counts are correct. They are done within the algorithm, not from the graphic. I made the site dots large enough to see and they overprint one another. Also many Vaganov and Schweingruber sites are colocated and one overprints another.

[…] excites you more, the engine research or the lead offering there — a link to a 4,400-word piece by Stephen McIntyre on enduring questions about the quality of analysis of a specific set of tree ring […]

[…] Climate Audit constructs a graph of growth. The red line is the growth rate of the small set of trees the Anthropogenic Global Warmists chose to use for their hockey stick of doom. The black line is growth rate for all of the trees that Stephan and Rachit cored while fighting off mosquitoes, including the vast majority of trees which the the Warmists somehow chose to not use. What the real data showed […]

[…] my word for it, do a bit of digging yourself. Below are just a few of my large list of sources. Yamal and Hide-the-Decline Climate Audit (and many similar) The Death Blow to Anthropogenic Global Warming by Stephen Wilde | Climate […]